During drive electric motors are heated whereby cooling is required in order to divert the heat. Cooling of electric motor may be effected by means of different types of cooling media such as e.g. air, water or oil.
U.S. Pat. No. 6,800,971 B1 discloses a device for liquid cooling of a stator for a start motor. The stator has a cooing channel formed between a housing surrounding the stator and a synthetic resin coated jacket surface of the stator back of the stator, wherein cooing is intended to be effected by means of a liquid cooling medium arranged to stream in the cooling channel such that cooling is effected directly towards the synthetic resin coated jacket surface of the stator back. The device has metal end plates welded at the respective end of the stator back.
EP 0434845 A1 discloses a device for liquid cooling of a stator. The core of the stator bears against a jacket provided with cooling channels in which liquid is arranged to stream. At the end of the stator core sealing rings are arranged. An adhesive having a sealing function exists between the stator laminates.
A problem with certain high performance electric motors is that the winding temperature becomes too high which may lead to damages on the electric motor, and for protecting the electric motor the current needs to be reduced wherein performance of the electric motor is impaired.
Further it is difficult to provide good contact between the stator of the electric motor and cooling portions resulting in a substantially impaired heat transfer and thereby impaired performance due to undesired temperature increase of the stator.